Grinding and polishing apparatus



March 22, 1938. w. a AKANS 2,111,955

GRINDING AND POLISHING APPARATUS Filed Aug. 27, 1936 INVENTOR WE. Ahmw vATTORNEY Patented Mar. 22, 1938 barren *sra'les Lemar creme My inventionrelates. to grinding and polishing apparatus and contemplates theprovision of apparatus of this kind adapted for use in producing highlyfinished surfaces on valve seats and the like, and has for an object theprovision 10f a device which may be readily mounted in'a drill press,boring mill, or the like for rotational movement to-grind or polishsurfaces. I

My invention further contemplates the provision of a device of this kindprovided with flexible coupling means adapted to overcome inaccuracy inthe alignment of the work in the machine.

My invention further contemplates the provision of a grinding andpolishing apparatus embodying means by which the working pressure of thefinishing elements upon the work may be readily regulated by theoperator.

My invention further contemplates the provision of grinding andpolishing apparatus in which the plate bearing the finishing elements isremovable therefrom for assembly therewith inside a valve. 7

My invention further contemplates the provision of a grinding andpolishing apparatus provided, with improved means for mounting thefinishin material, such as cloth covered with abrasive material, inWorking position on the device.

My invention embodies other novel features, details of construction, andarrangement of parts which are hereinafter set forth in thespecification and claims and shown in the accompanying drawing.

Apparatus embodying features of my invention is illustrated in theaccompanying drawing,

forming part of this application, wherein:

Fig. 1 is a View in side elevation of my improved grinding and polishingdevice, the plate employed to carry the finishing elements being removedtherefrom;

Fig. 2 is a sectional View taken along the line II-II of Fig. 3, showingthe working plate having a pair of finishing members attached thereon;

Fig. 3 is a plan view of the working plate;

Fig. 4 is a sectional view taken along the line IV-IV of Fig. 1;

Fig. 5 is a sectional view taken along the line V-V of Fig. 1;

Fig. 6 is a sectional View taken along the line VI-VI of Fig. 2; and

Fig. 7 is a sectional view taken along the line VII-VII of Fig. 4. v

Referring now to the drawing for a better understanding of my invention,I show a grinding attachment plate I 2.

andpdlishihg apparatus comprising a shaft 8 which is adaptedto'be-rotated by any suitable 'mieansx On the lower end of the shaft isformed a shoulder or flange portion. 9 which is snugly fitted formovement in a recess II formed in the The attachment plate is providedwith an inwardly turned flange portion ill for engagement with theshoulder 9 when same is in its upper position.

The shaft is slotted at l3 above the shoulder portion 9 to receive adriving plate M- which rests uponthe flange it and between theprojections 56 of the attachment plate. A pivot point ll is also mountedin the slot l3 and is held against displacement by a collar l8 whichforms a spring seat for the lower end of the spring it. A sleeve 2| issecured to the upper end of the shaft by means of the set screw 22 andis threaded at 23 to receive an internally threaded adjustment theworking plate and are formed with grooves 33 adapted to receive theflange 3 2 of the locking collar. The attachment plate and lockingcollar are slotted at 36 and 37 respectively to receive the lockingpins.

The plate 2? is formed with a plurality of slots 33, each of which isadapted to receive the upright portion 39 of an abrasive holder ll. Theholders 4! are held in position by means of screws 42 and are groovedalong their sides at as to receive the ends of an abrasive strip 34which is held against displacement by clips 55 formed of spring wire andpivotally mounted at 36. While the holders illustrated in the drawingare adapted for use in grinding and polishing fiat valve seats, otherforms may readily be mounted on the plate for use in finishing taperedvalve seats. When employed in the finishing of fiat valve seats, thebottom of each of the holders t! is preferably formed convex to providea line contact between the abrasive strips and the work.

A centering point 41 is provided on the end of the shaft for use inaligning the work in the machine, and a spring pressed ball 48 isprovided in the attachment plate for engagement in notches 49 formed inthe locking collar 3|.

The attachment plate l2 and the locking collar 3| are formed withaligning slots 49 adapted to receive a spring locking member 5| to holdcollar in position on the attachment plate.

In the operation of the apparatus thus described, the shaft 8 is adaptedto be rotated by a drill press or the like and.- a downward pressure isexerted upon the shaft to place the spring 19 under compression.Rotational movement is transmitted from the shaft to the working plate21 by means of the driving plate l4 engaging the projections l6 formedon the attachment plate l2. As it is very difiicult to align the work atexactly right angles to the aXis of the shaft 8, I have provided theflexible connection between the shaft and the working plate M in which,the downward pressure upon the shaft is directed to the working platethrough a one point contact provided by the pivot point I! and therotational movement is through the driving plate I4 and attachment platel2. The pressure of the abrasive strips 44 upon the work may readily bevaried by turning the adjustment sleeve 24.

While I have shown my invention in but one form, it is obvious to thoseskilled in the art that it is not so limited but is susceptible ofvarious changes and modifications without departing from the spiritthereof; and I desire, therefore, that only such limitations shall beplaced thereupon as are imposed by the prior art.

I claim:

1. In a grinding and polishing apparatus, a driving shaft, an attachmentplate mounted for axial movement on said driving shaft, a compressionspring mounted on the driving shaft to yieldably resist an axialmovement of the attachment plate along the driving shaft, a pivot pointinterposed between the compression spring and the attachment plate, aworking plate, work finishing elements mounted on the working plate,clip means for holding strips of abrasive material on the work finishingelements, means for detachably connecting the working plate to theattachment plate and means for varying the resistance offered by thecompression spring when the attachment plate moves inwardly.

2. In a grinding and polishing apparatus, a driving shaft, an attachmentplate mounted for axial movement on said driving shaft, spring means toyieldably resist an axial movement of the attachment plate along thedriving shaft, a pivot point interposed between the spring means and theattachment plate, a working plate, a work finishing element mounted onthe working plate, means for detachably connecting the working plate tothe attachment plate and means for varying the resistance offered by thespring means when the attachment plate moves inwardly.

WILLIAM R. AKANS.

